I've been given the task of setting up a linux webserver, but the boss wants a simple to use interface to manage sites and user accounts from a web based interface. Its replacing an array of RaQ servers which are linux based, but have a management interface to setup sites, FTP access, enable PHP for different sites, do virtual sites, enable FP extensions and etc.

Is there an open source web management program I can run? I can explain more if this description doesn't make sense...